(invertebrate zoology)
The stem sawflies, composing the single family of the hymenopteran superfamily Cephoidea.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(stem sawflies), a family of hymenopterous insects that are pests of cereal plants. The two most harmful species are the wheat stem sawfly (Cephus pygmaeus) and Trachelus tabidus. The wheat stem sawfly is distributed in North America and Europe. In the USSR it is found mainly in the steppe and forest-steppe zones, but it has reached as far as Leningrad Oblast. Trachelus tabidus is found in the south, in the steppe zone of the European part of the USSR. The larvae of the Cephidae damage the stems of many cereal grains, as well as awnless bromegrass, orchard grass, timothy, and wild oats.

Adult larvae winter in the lower part of the stem. In the steppe zone the wheat stem sawfly hatches at the beginning of the heading stage of winter wheat, and Trachelus tabidus 12 to 20 days later. The insects feed for some time on the nectar of the flowers; then the females, after boring through the stem with their ovipositors, lay their eggs in the cavity of the upper parts of the stems. As the larvae feed inside the stems, they destroy part of the vessels that conduct water, and the grain diminishes in weight, as well as in quality. More of the plants with bored-through stems fall, and the fodder quality of the straw deteriorates.

Control measures consist in the careful disking of the stubble and deep autumn moldboard plowing. In all, plowing will kill up to 60 percent of the larvae. Other control measures include the early sowing of spring cereal crops, windrow harvesting of wheat, planting of wheat varieties with developed stems, and early harvesting of cereals.


See references under .


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
Mentioned in ?
References in periodicals archive ?
The gall-inducing Cecidomyiidae seems to have evolved directly from detritivorous/mycetophagous ancestors, while other insect groups have evolved from: spores/pollen feeders (such as Thysanoptera: Phloeothripidae); plant sap feeders (as Hemiptera: Adelgidae, Eriosomatidae, Psyllidae, and Coccidae); foliage feeders (as Coleoptera: Curculionidae and Hymenoptera: Tenthredinidae); stem borers (as Hymenoptera: Cephidae); leaf miners (as Lepidoptera: Gelechiidae, and Diptera: Tephritidae and Agromyzidae); and from zoophage parasitoids (as Hymenoptera: Cynipidae) (Roskam, 1992).
The investigation of Beauveria bassiana (Ascomycota: Hypocreales) as a biocontrol agent of rose-stem sawfly, Syrista parreyssii (Spinola, 1843) (Hymenoptera: Symphyta; Cephidae) larvae.
Sing et al., "Within-field spatial distribution of Cephus cinctus (Hymenoptera: Cephidae) larvae in Montana wheat fields," Canadian Entomologist, vol.
The effect of the wheat stem sawfly, Cephus Cinctus (Hymenoptera: Cephidae), on the yield and quality of wheat.
. 1989 Separation of four Chlorocytus species (Hymenoptera: Pteromalidae), parasitoids of stem-boring Hymenoptera (Eurytomidae and Cephidae) using enzyme electrophoresis.